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arXiv · 1211.0621

Full groups and soficity

Gabor Elek
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Abstract

First, we answer a question of Pestov, by proving that the full group of a sofic equivalence relation is a sofic group. Then, we give a short proof of the theorem of Grigorchuk and Medynets that the topological full group of a minimal Cantor homeomorphism is LEF. Finally, we show that for certain non-amenable groups all the generalized lamplighter groups are sofic.

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Gabor Elek. 2012-11-18. Full groups and soficity. https://arxiv.org/abs/1211.0621

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